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Rapid industrial growth is associated with an increase in the production of environmentally harmful waste. A potential solution to significantly reduce pollution is to replace current synthetic materials with readily biodegradable plastics. Moreover, to meet the demands of technological advancements, it is essential to develop materials with unprecedented properties to enhance their functionality. Polysaccharide composites demonstrate significant potential in this regard. Polysaccharides possess exceptional film-forming abilities and are safe for human use, biodegradable, widely available, and easily modifiable. Unfortunately, polysaccharide-based films fall short of meeting all expectations. To address this issue, the current study focused on incorporating carbon quantum dots (CQDs), which are approximately 10 nm in size, into the structure of a starch/chitosan biocomposite at varying concentrations. This modification has improved the mechanical properties of the resulting nanocomposites. The inclusion of nanoparticles led to a slight reduction in solubility and an increase in the swelling degree. The optical characteristics of the obtained films were influenced by the presence of CQDs, and the fluorescence intensity of the nanocomposites changed due to the specific heavy metal ions and amino acids used. Consequently, these nanocomposites show great potential for detecting these compounds. Cellular viability assessments and comet assays confirm that the resulting nanocomposites do not exhibit any cytotoxic properties based on this specific analytic method. The tested nanocomposites with the addition of carbon quantum dots (NC/CD II and NC/CD III) were characterised by greater genotoxicity compared to the negative control. The positive control, the starch/chitosan composite alone, was also characterised by a greater induction of chromatin damage in mouse cells compared to a pure mouse blood sample. [ABSTRACT FROM AUTHOR]

Frequent occurrence of microbial resistance to biocides makes it necessary to find alternative antimicrobial substances for modern veterinary medicine. The aim of this study was to obtain biodegradable silver nanoparticle-containing (AgNPs) foils synthesized using non-toxic chemicals and evaluation of their activity against bacterial pathogens isolated from oral cavities of cats, dogs and horses. Silver nanoparticle foils were synthesized using sodium alginate, and glucose, maltose and xylose were used as reducing agents. The sizes of AgNPs differed depending on the reducing agent used (xylose < maltose < glucose). Foil without silver nanoparticles was used as control. Bacterial strains were isolated from cats, dogs and horses by swabbing their oral cavities. Staphylococcus aureus, methicillin-resistant Staphylococcus aureus (MRSA), Escherichia coli and extended-spectrum beta-lactamase (ESBL) producing E. coli were isolated on selective chromogenic microbiological media. The bactericidal effect of AgNPs foils obtained using non-toxic chemical compounds against E. coli, ESBL, S. aureus and MRSA isolated from oral cavities of selected animals was confirmed in this study. No statistically significant differences were observed between the foils obtained with different reducing agents. Therefore, all types of examined foils proved to be effective against the isolated bacteria. [ABSTRACT FROM AUTHOR]

For the last years scientific community has witnessed a rapid development of novel types of biomaterials, which properties made them applicable in numerous fields of medicine. Although nanosilver, well-known for its antimicrobial, anti-angiogenic, anti-inflammatory and anticancer activities, as well as hyaluronic acid, a natural polysaccharide playing a vital role in the modulation of tissue repair, signal transduction, angiogenesis, cell motility and cancer metastasis, are both thoroughly described in the literature, their complexes are still a novel topic. In this review we introduce the most recent research about the synthesis, properties, and potential applications of HA-nanosilver composites. We also make an attempt to explain the variety of mechanisms involved in their action. Finally, we present biocompatible and biodegradable complexes with bactericidal activity and low cytotoxicity, which properties suggest their suitability for the prophylaxis and therapy of chronic wounds, as well as analgetic therapies, anticancer strategies and the detection of chemical substances and malignant cells. Cited studies reveal that the usage of hyaluronic acid-silver nanocomposites appears to be efficient and safe in clinical practice. [ABSTRACT FROM AUTHOR]

Nanocomposite materials are increasingly commonly used to ensure food safety and quality. Thanks to their unique properties, stemming from the presence of nanoparticles, they are used to develop advanced sensors and biosensors, e.g., for various harmful substances, heavy metals, microorganism growth, and environmental changes in food products. The aim of this study is to produce novel films based on natural resources—potato starch and chitosan—incorporating generated quantum dots of zinc sulfide and cadmium sulfide. The biocomposites were subjected to the following assays: FTIR spectroscopy, UV-VIS spectroscopy, photoluminescence spectroscopy, and SEM/TEM spectroscopy. Their mechanical properties were also analyzed, a colorimetric analysis was performed, and the water content, solubility, and water absorption capacity were determined. A storage test was also performed, using poultry meat covered with the produced films, to assess the microbiological quality. The results confirmed the presence of the quantum dots in the starch–chitosan matrix. The unique optical properties of the films were also demonstrated. It was shown that the composites with nanoparticles limited the growth of selected microorganisms in poultry meat. The food storage time was found to have an impact on the fluorescent properties of the composites. The results point to the possibility of using the produced films as active and smart packaging. [ABSTRACT FROM AUTHOR]

Natural polysaccharides, including hyaluronic acid, find a wide range of applications in biomedical sciences. There is a growing interest in nanocomposites containing hyaluronic acid and nanoparticles such as nanometals or graphene. In this study, we prepared foils of pure sodium hyaluronate and sodium hyaluronate containing nanosilver, graphene oxide, nanosilver/graphene oxide and characterized their properties. UV-vis spectroscopy and scanning electron microscopy (SEM) confirmed the formation of 10–20 nm silver nanoparticles. The structural changes were investigated using Fourier transforms infrared (FTIR) spectra and size exclusion chromatography. The obtained results suggest changes in molecular weights in the samples containing nanoparticles, which was highest in a sample containing nanosilver/graphene oxide. We also assessed the mechanical properties of the foils (thickness, tensile strength and elongation at break) and their wettability. The foils containing nanosilver and nanosilver/graphene oxide presented bacteriostatic activity against E. coli, Staphylococcus spp. and Bacillus spp., which was not observed in the control and sample containing graphene oxide. The composites containing graphene oxide and nanosilver/graphene oxide exhibited a cytotoxic effect on human melanoma WM266-4 cell lines (ATCC, Manassas, VA, USA). [ABSTRACT FROM AUTHOR]